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What is the hydraulic force needed to lift a car?

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What force must be applied to a small cylinder piston with a diameter of 0.32 m to lift a car weighing 12,000N that is supported by the piston in a large cylinder that has a diameter of 1.4m? Assume that there is a closed chamber in the common between the two pistons and that the chamber is filled with hydraulic oil.

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The hydraulic presses work on the principle that the pressure is the same in all points (if we neglect small differences in hight) and the pressure is the same in all directions.
Therefore if we know ...

Solution Summary

This solution provides the formula and step by step calculations for determining the requested force.

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"Jobbed" by Philip Levine

Briefly describe perspectives of diversity, personal integrity, or social justice in the workplace that you think are present in the selected reading.

Jobbed
Philip Levine

In the summer of 1944 the was almost five years old, my older brother was in England with the Eighth Air Force, but home life went on as though it were all that mattered. I was sixteen, about to enter my junior year of high school, and working for an automotive parts manufacturer and jobber on Detroit's Grand River Avenue. I needed the job in order to earn money to clothe myself for the coming school year, and since I had become aware of the presence of girls in my classes I yearned for clothes that would make me attractive. I also had to feed another passion I'd discovered two years earlier: horse racing, at which I did only slightly better. It wasn't a great job, but it was the best I could do, for I was small for my age, not much over five foot four, and I weighed less than a hundred and thirty-five pounds. The boss assigned me to work under the direction of Andrew Griffin, the truck driver and general handyman around the shop, which employed fewer than two dozen people, half of them women who assembled universal joints, work that required quick and precise hands rather than brute strength.
Andy griffin was unlike anyone else I'd even known. In truth, in the fifty years since then, I don't think I've met anyone who resembled Andy. He was not that much taller than I, perhaps five foot ten, and I would guess he weighed about a hundred and eighty-five pounds. He wore coveralls or overalls to work and always long-sleeved shirts, even on blazing days, but it was easy enough to see he was powerfully built. Though thick through the shoulders and thighs, he moved with the grace and ease of someone much more slender. In physique and in his physical bearing he reminded me of the young Eric Hawkins, the great dancer. His skin was dark brown: his hair, just beginning to show touches of gray, was worn short. I would guess he was in his late thirties or early forties. His teeth were very regular and a sparkling white, and because he frequently smiled, one saw a lot of them. His eyes were dark brown and very bright. With his long oval face, the skin of which was very smooth, and his compact, neat features, he was truly beautiful, although I doubt he knew it, for he never showed the least trace of vanity. By Fridays his handsomeness was somewhat obscured by his graying stubble, for he shaved only on weekends.
The truck he drove was a two-and-a-half-ton stake truck, a Chevy, built in the late thirties, and for smooth operation it required double clutching, which Andy performed so rapidly he had to slow the process so that I could get a clear sense of what he was doing. Once I'd mastered that, he showed me how to back up through the most intricate mazes. Often, we visited the larger auto or auto parts factories to buy scrapped material, and the truck had to be maneuvered down narrow aisles of machines and the men who worked them. "Always go in backwards so you don't have to think about getting out," Andy advised me. In order to accomplish this, he'd put the truck in reverse, and with the clutch depressed with his left heel, he'd face backwards on the running board while he steered with his left hand, propelling the truck backwards by delicately letting the clutch out. He was both inside and outside the truck and driving it with great precision. The first time I saw him drive this way I was utterly stunned, and later when I asked him where he'd learned this method he said he couldn't remember. He probably taught it to himself, for I've never seen anyone else do it.
A great deal of what we did together involved the movement of large and often very heavy wooden crates that Andy and another employee, Eugene Watkins, created out of scrap wood. The shop had no forklift, and this was before trucks were equipped with hydraulic lifts on the tail, so I had to learn how to lift and carry in tandem with a man much stronger than I. I had to learn to balance a crate on one knee and turn so that I could face forward if we were going upstairs: and, bearing the brunt of the weight, could thus propel the crate and me together. When we descended, he would go first, the crate resting on his broad back as I scampered behind as fast as I was able. So precise and careful was he that not once during the long summer did I mash a finger or bruise an elbow. Every few days he would cheer me up by assuring me I was growing stronger and more adept, and after a few months passed it was clear even to me that he was right.
Andy created the rhythm of those days we spent together. If the driving wasn't difficult and he was tired, he'd let me take the wheel. If we had dozens of boxes and crates to load, he would choose the order in which we handled them and the configuration they made in the truck. He would work steadily and almost always in silence, and I would have to hop to it to keep up with him. When he sensed my exhaustion, he would call for a cigarette break. I remember once I took out a pack of matches just as he did and was about to tear one off when he said, "Save it. You don't know when you'll need it." (That moment was a sudden vision into his history and character.)
When Andy was hungry, or sensed I was, we'd break for lunch, which on pleasant days we took in the back of the truck, having brought our brown bags with us. Our allotted lunchtime was thirty minutes, and though no one was watching over us, that was exactly the time we took. Once, as we were smoking before returning to work, two men approached us. They were both dressed in ill-fitting ray suits and wore fedoras. We were parked just off West Warren near the Kelsey Hayes Plant, which was our next stop. One of the men called out, "Boy, do you know what time it is?" He seemed to be looking at Andy, who stood slowly and flicked his cigarette past the man and stood in silence for a long moment. "You shouldn't call my partner a boy," he said, "he's doing a man's work." The he looked at his pocket watch and said, "About one." The man thanked him, and they went on their way. "Most people would be nice," Andy said, "if they just knew how."
In late August, just before the end of summer vacation, the boss called me into his office and questioned me about a missing carton of very costly aircraft bearings. "Most of what goes in and out of the back door of this place goes through your hands," he said, "or Andy's." I suggested that someone could have misplaced it. No, he 'searched everywhere, and it wasn't here. I didn't believe him; the place was huge, maybe twenty thousand square feet. There were aisles of clutch plates, used bearings, drive shafts, and ancient Packard grills that no one ventured down for days at a time. "I can assure you it didn't go out the front door," he said. That left Andy and me on the loading dock at the rear. He dismissed me and told me to send Andy to the office. When he called me in again the next day, he threatened me with a phone call to the police. I assured him I had no idea where they were or even how one would go about selling such things. The boss, a less than totally Americanized immigrant from the Ukraine, ran a hand through his thick mane of white hair. "It's the nigger," he said. I was far more surprised by his lack of knowledge of Andy's character than by his language.
"Funny," Andy said less than an hour later, after a long session in the office. "Worked nine years for the man and he still don't trust me. Something's missing; it's got to be me. If I wanted to, I could take half the place out that back door," he added, gesturing toward the loading dock. We were in the back of the shop where I had been counting junk bearings out of a burlap sack. Beside me on the long wooden workbench, Andy was assembling his possessions slowly and placing them with great care into a large paper sack: a suit of coveralls, a pair of high lace-up boots for bad weather, a zip-up windbreaker, a few tools of his own - a claw hammer, a nail puller, pliers, and a large clasp knife. It was obvious he was leaving, but if he'd been fired or if he'd quit he didn't say. "Phil, you'll be OK," he said without looking my way, the single bare bulb that hung above us was so weak I could barely make out his features. "Some other driver will show you things I never had time to - maybe things I never learned." I'd never seen him move with such deliberation nor stand so erectly; it was as though he were on parade. When all his personal items were stowed, he turned to me, and I could see that his eyes were clear. We shook hands, and he walked out of my life. Less than a week later, the missing bearings turned up in the trunk of the boss's car.

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